Door locking and unlocking apparatus

ABSTRACT

THIS DISCLOSURE DESCRIBED AN APPARATUS FOR AIDING THE LOCKING OR UNLOCKING OF A DOOR CLOSED AND OPENED BY AN OFF-CENTER MECHANISM. THE APPARATUS INCLUDES A LOCKABLE DOOR HANDLE MOUNTED OUTSIDE OF THE DOOR TO BE LOCKED. THE LOCKABLE DOOR HANDLE IS CONNECTED BY A CONTROL ROD OR A FLEXIBLE CABLE TO A BELL CRANK OR CAM MECHANISM. ATTACHED TO THE BELL CRANK OR CAM MECHANISM IS A SLIDEABLE ROD, STRIP, OR PLATE. THE BELL CRANK OR CAM MECHANISM IS ROTATED WHEN THE CONTROL ROD IS MOVED BY THE ROTATION OF THE LOCKABLE DOOR HANDLE. WHEN THE BELL CRANK MECHANISM IS ROTATED, THE SLIDEABLE ROD, STRAP OR PLATE IS MOVED TOWARD THE OFF-CENTER MECHANISM. THE ENDS OF THE ROD, STRAP OR PLATE INCLUDE RUBBER BUMPERS WHICH IMPINGE ON THE HANDLE OF THE OFF-CENTER MECHANISM AND MOVE IT FROM ITS OFFCENTER LOCKED POSITION OR ITS OFF-CENTER UNLOCKED POSITION AS THE CASE MAY BE. THEREAFTER, THE DOOR CAN BE UNLOCKED OR LOCKED BY SIMPLY PUSHING IT OPEN OR CLOSED AS DESIRED.

Sept. 21, 1971 E. E. DAVIS DOOR LOCKING AND UNLOCKING APPARATUS 6 Sheets-Sheet 1 Filed Oct. 24, 1969 INVENTOR Earl E. Davis A TTORN E YS Sept. 21, 1971 E. E. DAVIS 3,606,?

DOOR LOCKING AND UNLOCKING APPARATUS Filed Oct. 24, 1969 6 Sheets-Sheet 2 INVENTOR Earl E. Qavis ATTORNEYS Sept. 21, 1971 E. E. DAVIS 3,606,700

DOOR LOCKING AND UNLOCKING APPARATUS Filed Oct. 24, 1969 6 Sheets-Sheet 3 nv VENTOR Earl E. Davis n9 BY m'fih'. BMZIWI/ ATTORNEYS E. E. DAVIS DOOR LOCKING AND UNLOCKING APPARATUS Sept. 21, 1971 6 Sheets-Sheet 4.

Filed Oct. 24, 1969 INVENTOR Eur! E. Davis ATTORNEY Sept. 21, 1971 E. E. DAVIS 3,606,700

DOOR LOCKING AND UNLOCKING APPARATUS Filed Oct. 24, 1969 6 Sheets-Sheet mv ENTOR EARL E. DAVIS Sept. 21, 1971 E. E. DAVIS DOOR LOCKING AND UNLOCKING APPARATUS 6 Sheets-Sheet 6 Filed Oct. 24, 1969 ATTORN EYS United States Patent 3,606,700 DOOR LOCKING AND UNLOCKING APPARATUS Earl Eugene Davis, Box 21, Guernsey, Wyo. 82214 Continuation-impart of abandoned application Ser. No.

776,544, Nov. 18, 1968. This application Oct. 24, 1969,

Ser. No. 871,508

Int. Cl. E05b 65/06 US. Cl. 49-394 26 Claims ABSTRACT OF THE DISCLOSURE This disclosure described an apparatus for aiding the locking or unlocking of a door closed and opened by an oft-center mechanism. The apparatus includes a lockable door handle mounted outside of the door to be locked. The lockable door handle is connected by a control rod or a flexible cable to a bell crank or cam mechanism. Attached to the bell crank or cam mechanism is a slideable rod, strap, or plate. The bell crank or cam mechanism is rotated when the control rod is moved by the rotation of the lockable door handle. When the bell crank mechanism is rotated, the slideable rod, strap or plate is moved toward the ofi-center mechanism. The ends of the rod, strap or plate include rubber bumpers which impinge on the handle of the ofi-center mechanism and move it from its offcenter locked position or its oif-center unlocked position as the case may be. Thereafter, the door can be unlocked or locked by simply pushing it open or closed as desired.

BACKGROUND OF THE INVENTION This application is a continuation-in-part of US. patent application, Ser. No. 776,544, filed Nov. 18, 1968 for Door Locking and Unlocking Apparatus, nOW abandoned.

Many doors particularly those in school busses, are opened and closed by an off-center mechanism. This mechanism generally includes a mounting member located near the drivers seat on the bus. A rotatable handle that moves toward and away from the driver is attached to the mounting member. A rod is attached to the handle at one end and, at the other end, is attached to the door. The axes of the handle, the center of rotation of the haudle about the mounting member, and the rod are slightly off-center. Because of this oif-center arrangement, the handle can be moved to locked and unlocked positions where pressure on the door will not move it. However, when the handle is in an in-between position, pressure on the door can open or close it.

The problem with an off-center door opening and closing mechanism is that it cannot be locked or unlocked from outside of the bus. The normal procedure for locking an off-center door opening and closing mechanism is to lock it from inside of the bus by placing it in its closed off-center position. There after, the person locking the bus exits through an emergency bus exit which is locked with a conventional key lock arrangement. It will be appreciated that this is undesirable, since in many cases the emergency exit is inconvenient, because it is high off the ground, freezes shut in the winter, is dilficult to operate and is only intended for emergency use. Consequently, many people with busses having off-center door closing and opening mechanisms do not lock them. Rather normally, the door is closed to a slightly ajar (not locked) position by pushing on it from the exterior of the bus. When it is desired to open the door, a counter push is used. It Will be appreciated that closing a bus in this manner is undesirable for a number of reasons. For example, because the bus is not locked, any person desiring to get into it for undesirable motives can easily do so. In addi- 3,605,700 Patented Sept. 21, 1971 ice tion, because the door is ajar, dust and snow and similar particles can enter the cracks located around the ajar door.

Therefore, it is an object of this invention to provide an apparatus for locking an ofl-center door opening and closing mechanism.

It is also an object of this invention to provide an apparatus for releasing or tripping an olf-center door closing and opening mechanism that is inexpensive, does not prevent the operation of the off-center opening and closing mechanism, and is suitable for easy installation.

It is a further object of this invention to provide an apparatus for releasing or tripping an ofi-center door open ing and closing mechanism mounted in a bus that is easy to mount, is inexpensive to manufacture, and does not prevent the conventional operation of the off-center door opening and closing mechanism.

SUMMARY OF THE INVENTION In accordance with a principle of this invention, an apparatus for releasing or tripping an off-center door opening and closing mechanism is provided. The apparatus includes a lockable handle or lockable push button mounted outside of the door and connected to the off-center door opening and closing mechanism. The lockable handle or push button is connected by coupling means to a bell crank or cam assembly. The bell crank or cam assembly is connected to a slideable rod, strap or plate having a bumper mounted on an outer projection. The slideable rod, strap or plate and the bell crank or cam assembly are positioned so that the bumper comes in contact with the handle of the off-center door opening and closing mechanism.

In general, the procedure for locking and unlocking the door using the invention is as follows: the door is closed by rotating the lockable handle to move the bell crank or cam assembly which in turn moves the bumper against the olf-center door closing mechanism. This coaction moves the handle of the elf-center door opening and closing mechanism from its locked open position, allowing the door to be slammed or pushed shut. Shutting the door forces the oil-center door opening and closing mechanism into a locked closed position. To unlock the offcenter door opening and closing mechanism, the lockable handle is rotated or the push button is pushed. When this action occurs, the bell crank or cam assembly rotates and forces the bumper against the handle of the off-center door opening and closing mechanism. This coaction moves the handle of the off-center opening and closing mechanism from its locked position to a position where the door can be opened by pushing on it. It will be appreciated that the weight of the handle of the off-center door opening and closing mechanism is sufficient to swing that handle into a locked open or locked closed position as the case may be.

In accordance with another principle of this invention, a pair of bell crank assembleis and a pair of rods or straps and bumpers are attached to the coupling means. One bumper is mounted so as to coact with the handle of the off-center door opening and closing mechanism when it is in its locked closed position and the other is adapted to coact with the handle of the off-center door opening and closing mechanism when it is in its locked open position.

In accordance with a further principle of the invention, a separate coupling means is connected between the two bell crank assemblies and includes an aperture means so that when the handle is rotated in one direction, one bell crank assembly operates; and when the handle is rotated in the other direction, the other bell crank assembly operates.

In accordance with a still further principle of the invention, the coupling means is a flexible cable and a spring. The spring returns the cable to a desired position after the lockable handle is rotated and prevents the application of excess pressure.

In accordance with an alternative principle of this invention, the coupling means is a rod and a spring means. The spring means prevents the application of extreme pressures to the rod.

In accordance with yet another principle of this invention, a single bell crank assembly is attached to a plate having a pair of outwardly extending arms. The

arms are mounted and formed so as to impinge on the handle of the off-center opening and closing mechanisrnone arm when the door is locked open and the other arm when the door is locked closed. When the single bell crank mechanism is rotated the arms move outwardly and impinge on the handle of the off-center door opening and closing mechanism.

In accordance with still another principle of this invention, a cam replaces the bell crank and is used in combination with a plate having a pair of outwardly projecting arms. As the cam is rotated its lobe impinges on the plate and causes the arms to move outwardly.

It will be appreciated by those skilled in the art and others that the invention is a rather uncomplicated assembly for locking an elf-center door opening and closing mechanism. The door is locked by slamming the door shut to force the handle of the door opening and closing mechanism to rotate to a locked closed position. Thereafter, without the invention, it is impossible to open the door from the exterior of the bus without destroying the door. The invention provides a means for moving the handle of the off-center door opening and closing mechanism from its locked closed position to a position where the door can be opened by merely pushing on it. In addition, the invention provides a means for moving the handle from a locked open position from the exterior of the bus. Consequently, if the door is locked open when a person leaves the bus, he rotates the lockable handle or pushes the push button to move the olf-center door opening and closing mechanism to a position where the door can be locked by slamming it. Thereafter, if he desires to open the bus, he rotates the lockable door handle or pushes the push button to move the handle of the off-center door opening and closing mechanism to a position where the door can be opened by pushing on it.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing objects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description when taken in conjuction with the accompanying drawings wherein:

FIG. 1 is an upper pictorial diagram of an embodiment of the invention mounted in a bus wherein a portion of the bus and the off-center mechanism are illustrated in dashed lines and the invention is illustrated in solid lines;

FIG. 2 is a side pictorial diagram of the embodiment of the invention illustrated in FIG. 1 from the point of view illustrated by arrows 2--2;

FIGS. 3A and 3B are pictorial diagrams illustrating one embodiment of the bell crank mechanism of the invention;

FIG. 4 is a pictorial diagram of a lockable handle suitable for use with the invention;

FIG. 5 is a pictorial diagram of the olf-center rotating mechanism connected to the lockable handle of FIG. 3 as viewed along lines 55 of FIG. 4;

FIG. 6 is an upper pictorial view of an alternative bell crank mechanism suitable for use with the invention;

FIG. 7 is an illustration of an alternative embodiment of the invention;

FIG. 8 is a further alternative em odiment of the mventlon;

FIG. 9 is a pictorial diagram of a spring mechanism suitable for use with the invention when the coupling means is a flexible cable;

FIG. 10 is a pictorial diagram of a spring mechanism suitable for use with the rod embodiments of the invention;

FIG. 11 is an alternative embodiment of a spring mechanism suitable for use with a rod embodiment of the invention;

FIG. 12 is a pictorial diagram of a push button mounting suitable for use with the invention;

FIG. 13 is a pictorial diagram of an alternative push button mounting suitable for use with the invention;

FIG. 14 is a pictorial diagram of still another push button mounting suitable for use with the invention;

FIG. 15 is a bottom view of yet another embodiment of the invention showing the invention connected to a locked closed door;

FIG. 16 is a bottom view similar to FIG. 15 showing the same embodiment of the invention connected to a slightly ajar door;

FIG. 17 is a front view of the embodiment of the invention illustrated in FIGS. 15 and 16;

FIG. 18 is a perspective view of a plate and bell crank assembly forming a portion of the embodiment of the invention illustrated in FIGS. 15 and 16;

FIG. 19 is a cross-sectional view along line 19--19 of FIG. 16;

FIG. 20 is a bottom view of the embodiment of the invention illustrated in FIGS. 15 and 16 where the handle of the off-center door opening and closing mechanism is in a locked open position;

FIG. 21 is a bottom view of still another embodiment of the invention;

FIG. 22 is a bottom view similar to FIG. 21 where the arms of the plate are extending outwardly; and

FIG. 23 is a cross-sectional view along line 23-23 of FIG. 22.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to the drawings wherein like reference numerals designate like parts throughout the several views, FIG. 1 is an upper view and FIG. 2 is a front view of one embodiment of the invention mounted in a bus. The bus and the off-center door opening and closing mechanism are illustrated in dashed lines, while the invention is illustrated in solid lines in FIG. 1. Further, only a portion of the bus is illustrated. The portion of the bus illustrated in FIGS. 1 and 2 includes the front of the bus 21 having a dashboard 23. A door 25 is illustrated as connected by a shaft 27 to an off-center door opening and closing mechanism 29. The off-center door opening and closing mechanism 29 includes a mounting member 31 connected to the dashboard 23 by suitable mounting means such as bolts, for example. The off-center door opening and closing mechanism also includes a handle 33 having a handle operating member 35 and a lower member 37 connected to the shaft 27. The handle is rotatably connected to the mounting member 31 by a rod 39 which may be a bolt, for example.

In a conventional manner, when the handle operating member 35 is moved, the handle rotates around rod 39 and the shaft 27 moves back and forth, as illustrated by the double headed arrow. As the shaft 27 moves back and forth, the door 25 opens and closes. More specifically, the door 25 is normally hinged at the front and in the center, or hinged on both sides and split in the center. When the shaft is moved, a hinge action occurs causing compression of the door against the front of the bus near the dashboard 23. When the handle is moved in the opposite direction, the door is moved to the closed position, illustrated in FIG. 1.

The embodiment of the invention illustrated in FIG. 1 comprises a lockable handle 41 connected by a coupling means such as a rod 43 to right and left bell crank assemblies 45 and 47. As illustrated in FIGS. 3A and 3B, each bell crank assembly includes a shaft 49, an outwardly projecting line 51 fixedly attached to the shaft 49, such as by welding, for example, and a backwardly projecting link 53 also fixedly connected to the shaft 94 by welding, for example. Each of the backwardly extending links 53 have a plurality of apertures 55 (FIG. 8') to which coacting links are connected. The upper end of the shaft 49 is mounted in a bearing (not shown). The bearing is mounted in a U-shaped upper attachment plate 59. The upper attachment plate includes a pair of apertures so that it can be attached under the dashboard 23 of the bus. In addition, an inverted U-shaped member 61 coacts with a head 62 on the shaft 49 for preventing the shaft from sliding out of the bearing. A coiled spring 57 is attached to the shaft inside of the inverted U-shaped member 61 to provide a return torque.

The rod 43 is rotatably connected to the outwardly extending links 51 by a pin or bolt. Consequently, as the shaft 43 is moved back and forth, the shafts 49 rotate in the bearings (not shown). Attached to the backwardly extending links 53 are slideable links 63. The slideable links 63 are rotatably attached to the backwardly extending links 53 by pins or bolts. The slideable links 63 are slideably mounted in front plates 67. The front plates 67 have apertures 69 so that they can be attached to the front of the body 31 by any suitable means, such as bolts, for example.

It will be appreciated from the foregoing description of the connections between the bell crank and its attached links, the slideable links and the rod 43, that as the rod 43 moves back and forth, the bell crank rotates. The rotation of the bell crank moves the slideable links 63 inwardly and outwardly with respect to the front of the dashboard 23. Mounted on the end of the slideable links 63 are bumpers 71 which may be formed of rubber or other similar semi-elastic materials.

As best illustrated in FIG. 2, the bumpers 71 connected to the slideable links are mounted so as to coact with the handle 33 of the off-center door opening and closing mechanism. That is, when the handle operating member 35 is locked in the door open or door closed positions, one or the other of the bumpers 71 is in a coacting position. More specifically, if the handle is in its door open locked position, the right bumper (as viewed in FIG. 1) coacts with it and, if the handle is in its door closed locked position, the left bumper coacts with it.

FIGS. 4 and 5 illustrates an apparatus for connecting the lockable handle 41 to the rod 43. The lockable handle 41 is connected by a cross-sectionally square shaped rod 72 to a plate 73 having a square aperture 75 through which the cross-sectionally square shaped rod 72 projects. The plate is attached to the rod 43 at a point offset from the location of the square aperture 75. Hence, as the lockable handle 41 is rotated, the shaft 72 rotates and moves the end of the plate back and forth. Since the end of the plate is connected to the rod 43, the rod 43 moves back and forth as the plate moves back and forth.

The lockable handle 41 contains a key operated lock 77. The lock mechanism is conventional and locks the handle so that it cannot be rotated. Alternatively, the lock mechanism could disengage the handle from the square shaped rod 72 so that when the handle is turned, the rods remain stationary. In either manner, locking of the lock 77 prevents the lockable handle 41 from moving the rod 43.

Turning now to the description of the overall operation of the invention, initially the door is in a locked open position and the person desiring to lock the bus is outside of the bus. When the door is in the locked open position, the handle 33 has been rotated to the right (as viewed in FIG. 1) as far as possible. To move the handle from the locked open position, the lockable handle 41 is rotated so that the rod 43 moves to the left and the slideable links move outwardly. When the right slideable link moves outwardly, the right bumper coacts with the handle 33 and moves the handle out of its locked open position. This action moves the door slightly closed. Thereafter, the person locking the bus moves the door to a closed position by pushing on the door, and as he does so, the handle 33 swings to the left until it reaches the locked closed position. That is, if a sufficient amount of pressure is put on the door 25 such as by pushing on a handle attached to the door, for example, the handle 33 of the off-center open and closing mechanism swings to a locked closed position. Now the door is locked closed and cannot be opened by pulling on the handle attached to the door. The person locking the bus now locks the lockable handle 41 through a conventional key mechanism. The bus is now completely locked.

Thereafter, when it is desired to open the bus, the person unlocks the lockable handle 41 and the lockable handle 41 is rotated. When the lockable handle 41 is rotated, the left slideable link moves outwardly against the handle 33. This action moves the handle 33 from its door closed locked position. Thereafter, the door 25 is opened by merely pulling on the leading edge of the door or pushing on the center hinge of the door.

It will be appreciated from the foregoing description of the apparatus of the invention, and its use, that a rather uncomplicated apparatus for aiding the locking of an offcenter door opening and closing mechanism is provided. Basically, the system requires bell crank assemblies connected by a rod to a lockable door handle. If the door is locked open when a person leaves the bus, he can easily move the door handle out of the locked open position and then lock the bus by pushing on or slamming the door. Thereafter, if he desires to obtain entrance into the bus, he merely rotates the lockable door handle to move the handle of the door opening and closing mechanism to an unlocked position. Then, the door is opened by pulling on The system illustrated in FIGS. 1 and 2 operates so that as the rod 43 is moved to the left, the slidable links 63 move outwardly. FIG. 6 illustrates an alternative embodiment wherein the rod is moved to the right to move the links outwardly. More specifically, in FIG. 6 the backwardly projecting link 53 of FIG. 1 is replaced by a forwardly projecting link 79. And, the slidable link 63 is connected on the left side of the shaft 49 as opposed to the right side of the shaft, as illustrated in FIG. 1. For this connection, the rod 43 is moved to the right to rotate the bell crank assembly and move the slidable link and its bumper outwardly. FIG. 6- also illustrates that a separate link member 81 can be used to connect the two bell crank assemblies as opposed to being connected by the common rod illustrated in FIG. 1.

The embodiments of the invention heretofore described have utilized a solid rod 43 for connecting the lockable handle 41 to the bell crank assemblies 45 and 47. As an alternative, FIG. 7 illustrates the use of a flexible cable 83 to connect the lockable handle 41 to the bell crank assemblies 45 and 47 The flexible cable 83 is connected to the left bell crank assembly 47 via a pulley 85 rotatably mounted to the left of the bell crank assemblies. A connecting rod '87 connects the outwardly extending links 51 of the bell crank assemblies. As heretofore discussed, the slidable links 63 with their bumpers 71 are connected via backwardly extending links 53 to shafts 49. The flexible cable 83 is moved to the right, as illustrated by the arrow in FIG. 7, by rotating the lockable handle 41. When the flexible cable is moved to the right, it pulls the rod 89 to the left. As the rod 89 moves to the left, the slideable links 63 and their attached bumpers 71 move outwardly. The outward movement of the slideable links operates to move the handle of 33 of the off-center door opening and closing mechanism from a door locked open or a door locked closed position, as the case may be.

FIG. 8 illustrates a further alternative embodiment of the invention wherein the lockable door handle 41 is rotated in one direction to move the right bell crank assembly 45 and in the other direction to move the left bell crank assembly 47. More specifically, the right bell crank assembly 45 includes the outwardly projecting link 51 and the backwardly projecting link 53. The 'backwardly projecting link 53 is connected to the slideable link 63 and its bumper 71. The left bell crank assembly includes the outwardly extending link 51 and a frontwardly extending link 79 (similar to the frontwardly extending link illustrated in FIG. 6). The slideable link 63 is connected to the frontwardly extending link 79. Upper attachment plates 59 for the shafts 49 are also illustrated in FIG. 8. In addition, front plates 67 for the slidable links 63 are illustrated. Connecting the two outwardly extending links 51 is a coupling rod 89. The coupling rod is connected by pins 91 to the outwardly extending links in longitudinal apertures. That is, the coupling rod 89 contains two longitudinal aperturesone aperture is connected by a pin 91 to one outwardly extending link 51 and the other aperture is connected by a pin to the other outwardly extending link. The longitudinal aperture connecting the outwardly extending link 51 of the front bell crank assembly projects toward the left bell crank assembly, while aperture connecting the outwardly extending link 51 of the left bell crank assembly projects toward the right bell crank assembly. Hence, as the rod 43 is moved in one direction or the other, only one bell crank assembly operates. It will be appreciated that the pins are adapted to slide in the apertures.

One possible problem with the invention is that excess pressure may be placed on the rod 43 or flexible cable 83. And, excess pressure could break or warp the overall assembly. Hence, it is desirable to prevent the application of excess pressure. The invention provides means, as hereinafter described, to prevent the application of excess pressure. Specifically, springs are used in combination with the rod or flexible cable to take up excess pressure.

FIG. 9 illustrates a spring assembly that is suitable for use with the flexible linkage 83 illustrated in FIG. 7. The spring assembly illustrated in FIG. 9 comprises a coil spring 101 enclosing a U-shaped member 103. The U- shaped member 103 has outwardly projecting U-shaped links at one end that connect with one end of the coil spring. The flexible cable passes through the spring and the U-shaped member and is connected to the coil spring at the other end by looping around a pin 104, for example. The pin is connected to the coil spring. The cross member of the U-shaped member 103 is outside of the coil spring and is adapted for connection to the handle 41 via flexible cable extension 105, for example. In operation, as the handle 41 rotates, the spring compresses and takes up excess pressure. Hence, excess pressures cannot be placed on the flexible cable 43.

FIG. 10 illustrates a spring assembly suitable for use in the embodiment of the invention illustrated in FIG. 1. In FIG. 10 the plate 73 (for connecting the shaft 43 to the cross-sectionally square shaped rod 72 of the lockable handle 41) includes a rotatable member 111 spaced from the square shaped aperture 75. The rod 43 passes through the rotatable member 111. A washer 113 is located about the rod on the side of the rotatable member 11 remote from the bell crank assemblies. A coil spring 115 fits over the rod against the washer 113. The other end of the coil spring presses against a second washer 117 and a nut 119 fits over the end of the rod to force the two washers and the coil spring assembly against the rotatable member 111. In operation, as the handle 41 is rotated and the plate 73 moves, the spring 115 compresses thereby taking up excess pressure applied to the rod 43.

FIG. 11 is generally similar to 'FIG. 10, except that it has coil springs 115 and washer assemblies mounted on both sides of the rotatable member 111. Hence, this assembly is suitable for use with the double rotation embodiment of the invention illustrated in FIG. 8. The innermost washer of the embodiment illustrated in FIG. 8 in- 8 cludes a pin 119 for preventing the Washer from moving away from the inwardly projecting spring 115.

FIG. 12 illustrates a lockable push button embodiment of the invention and comprises: a lockable push button 131 mounted in a tubular case 133; a bracket 135; and an arm 137. The tubular case 133 and the bracket are attached to the side of a vehicle (bus) body 139 by bolts 141 so that the push button 131 extends outside of the vehicle and the bracket extends inside of the vehicle. The arm 137 is attached at one end to the inward end of the bracket in a pivoting manner, as illustrated by the circular arrow. The other end of the arm is attached to the rod 43. The push button includes an inwardly extending pin 143 that impinges on the arm at a point intermediate the ends of the arm. The tubular case 133 includes a coil sring 145 that is mounted between the inner end of the push button 131 and the inner end of the tubular case 133. The pin 143 extends through the coil spring 145.

In operation, when the push button 131 is pushed, the coil spring 145 compresses and the pin 143 moves the arm 137. When the arm moves, the rod 43 moves and operates the bell cranks in the manner heretofore described.

FIG. 13 illustrates a second lockable push button embodiment of the invention wherein the cable 83 is operated by a lockable push button. Generally, the FIG. 13 embodiment is similar to the FIG. 12 embodiment with the change that the arm 137 is pivotally mounted on the bracket 135 at a midpoint and the pin 143 impinges on the arm at one end. The other end of the arm 137 is attached to the cable 83. One or more sheaves 147 are illustrated and used to correctly align the cable 83 with the bell cranks.

FIG. 14 illustrates an alternative means for mounting the push button structure. Specifically, the exterior of the tubular case 131 is threaded and passes through an aperture in the vehicle body. The tubular case has a flanged outer edge that presses against the vehicle body. An aperture in the bracket 135 and a nut 149 pass over the threads and compress the flange against the vehicle body to hold the overall structure in place. It will be appreciated that the FIG. 14 mounting alternative eliminates the need for bolt holes in the vehicle body and, hence, makes mounting easier.

FIGS. 152O illustrate a further alternative embodiment of the invention and comrises a unitary bell crank 151 and a plate 153 having a pair of outwardly projecting arms 155 and 157. Preferably the bell crank is formed of an L-shaped piece of suitably rigid sheet metal. The junction of the L-shaped bell crank is attached to -a slot 159 in the plate 153 by a first bolt 151. The first bolt is also fixedly attached to the mounting member 31. One end of the L-shaped bell crank is attached to the rod 43 which is connected to the lockable handle 41. The other end of the L-shaped bell crank is attached by a second bolt 163 to a second slot in the plate 153. In operation, when the rotatable handle 141 is rotated, it moves the rod 43. Movement of the rod 43 rotates the L-shaped bell crank 151 about the first bolt 161. As illustrated in FIGS. l5, l6 and 20 this movement of the L-shaped bell crank causes the plate 153 to move back and forth. Movement of the plate 153 moves the arms 155 and 157 outwardly and inwardly. The arms have, as illustrated in FIG. 18 upwardly extending portions 165 which impinge on the oif center door opening and closing mechanism in the manner heretofore described. If desired, rubber bumpers can be attached to the upwardly extending members 165. Suitable slotted plates 167 adapted for attachment to the front of the dashboard of the bus are also illustrated in FIGS. 15-20. In addition, bumpers 169 and 171 are included for preventing the off center door opening and closing mechanisms handle 133 from smashing into the dashboard. The bumpers are mounted on the front plates 167 in any suitable manner, such as by bolts. Preferably,

the plate 153 and the arms 155 and 157 are formed of a suitably rigid sheet metal material.

FIGS. 21-23 illustrate still another alternate embodiment of the invention. The embodiment of the invention illustrated in FIGS. 21-23 includes a plate generally similar to the plate illustrated in the embodiments of FIGS. 15-20. This is, the plate 175 includes a pair of outwardly extending arms 177 and 179 having upwardly projecting portions 181. In addition, the arms pass through slotted plates 183 suitable for mounting on the front of the dashboard. The primary difference between this em bodiment and the just previously described embodiment is that the L-shaped bell crank is replaced by a cam 185 that is generally semi-circular in shape. A bolt 187 passes through a slot 189 in the plate 175, and is attached to the center of the cam 185 and the support member 31. The portion of the generally flat cam facing the interior of the bus impinges, as illustrated best in FIG. 23, on a generally U-shaped ,(in cross-section) portion 191 of the plate 175. The opposite edge of the cam 185 impinges on a pin 193 that passes through the plate 175. One end of the cam 1-85 is attached to the rod 43 which is connected to the lockable handle 41. As illustrated in FIGS. 21 and 22 as the lockable handle is rotated, the cam 185 rotates and moves against the 'U-shaped portion 191. This movement causes the arms 177 and 179 to move through the slots inthe face plates 183 and impinges on the handle of the off center door opening and closing mechanism 33 in the manner previously described.

It will be appreciated from the foregoing description that the invention is rather uncomplicated apparatus for locking an off-center door opening and closing mechanism. In addition to just locking the door, the invention also provides means for preventing excess energy from being applied to the rod or flexible cable connecting the lockable door handle to the apparatus for unlocking the off-center door opening and closing mechanism.

It will be appreciated by those skilled in the art and others that the foregoing description has only described preferred embodiments and that various changes can be made within the scope of the description. For example, the angle between the links attached to the shafts and forming a portion of the bell cranks has been illustrated in the drawings as 90. However, it will be obvious to those skilled in the art that other angular relations can be used. Hence, the invention can be practiced otherwise than is specifically described herein.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Apparatus for aiding the locking and unlocking of an oif-center door opening and closing mechanism including a handle and comprising:

lockable means suitable for mounting at a point exterior to the door operated by said off-center door opening and closing mechanism;

rotatable means for transferring power from one direction to a second direction;

coupling means for coupling said lockable means to said rotatable means; and

slidable means, attached to said rotatable means and mounted so as to coact With the handle of said olfcenter door opening and closing mechanism, for applying a force to the handle of said off-center door opening and closing mechanism at a predetermined point.

2. Apparatus for aiding the lock and unlocking of an off-center door opening and closing mechanism as claimed in claim 1 wherein said rotatable means comprises at least one hell crank.

3. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 2 wherein said at least one bell crank comprises a pair of hell cranks and said slidable means 10 comprises a pair of slidable links, one slidable link being connected to each of said pair of bell cranks.

4. Apparatus for aiding the locking and unlocking of an elf-center door opening and closing mechanism as claimed in claim 3 wherein said coupling means comprises a rod for coupling said pair of hell cranks to said lockable means.

5. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 4 including a spring operatively coupled to said lockable means and said rod to prevent the application of excess pressure to said rod when said lockable means is operated.

6. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 5 wherein each of said bell cranks comprises:

a rotatably mounted shaft;

a first link fixedly attached to said shaft at one end and rotatably attached to said rod at the other end; and

a second link fixedly attached to said shaft at one end and rotatably attached to a slideable link at the other end.

7. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 6 including a pair of bumpers formed of a semi-elastic material, one bumper being mounted on the end of each of said slideable links at the point .Where said slidable links coact with the handle of said door opening and closing mechanism.

8. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 3 wherein said coupling means comprises a flexible cable for coupling one of said pair of bell cranks to said lockable means and a rod for connecting said one of said pair of bell cranks to the other of said pair of bell cranks.

9. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 8 including a spring operatively coupled to said lockable means and said flexible cable to prevent the application of excess pressure to said flexible cable when said lockable means is operated.

10. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 9 wherein each of said bell cranks comprises:

a rotatably mounted shaft;

a first link fixedly attached to said shaft at one end and rotatably attached to said rod at the other end; and

a second link fixedly attached to said shaft at one end and rotatably attached to a slidable link at the other end.

11. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 10 including a pair of bumpers formed of a semi-elastic material, one bumper being mounted on the end of each of said slidable links at the point where said slidable links coact with the handle of said door opening and closing mechanism.

12. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanisms as claimed in claim 9 including longitudinal apertures in said rod at the point where said rod is attached to said first link of said bell cranks so that said rod can longitudinally move with respect to said bell cranks as well as rotate.

13. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 3 wherein said coupling means comprises a first rod for coupling one of said pair of bell cranks to said lockable means and a second rod for coupling said one of said pair of bell cranks to the other of said pair of bell cranks.

14. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 13 including a spring means operatively coupled to said lockable means and said first rod for preventing the application of excess pressure to said rod when said lockable means is operated.

15. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 12 wherein each of said bell cranks comprises:

a rotatably mounted shaft;

a first link fixedly attached to said shaft at one end and rotatably attached to said rods at the other end; and

a second link fixedly attached to said shaft at one end and rotatably attached to a slideable link at the other end.

16. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 15 including a pair of bumpers formed of a semi-elastic material, one bumper being mounted on the end of each of said slideable links at the point where said slideable links coact with the handle of said door opening and closing mechanism.

17. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 16 including longitudinal apertures in said second rod at the point where said second rod is attached to said first link of said bell cranks so that said second rod can longitudinally move with respect to said bell cranks as well as rotate.

18. Apparatus for aiding the locking and unlocking of an ofif-center door opening and closing mechanism as claimed in claim 2 wherein said at least one bell crank comprises one bell crank and said slideable means comprises a plate having a pair of projecting slideable arms, said plate being connected to said bell crank.

19. Apparatus for aiding the locking and unlocking of an oil-center door opening and closing mechanism as claimed in claim 18 wherein said coupling means comprises a rod for coupling said bell crank to said lockable means.

20. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 19 including a spring operatively coupled to said lockable means and said rod to prevent the 12 application of excess pressure to said rod when said lockable means is operated.

21. Apparatus for aiding the locking and unlocking of an ofi-center door opening and closing mechanism as claimed in claim 20 wherein said bell cranks comprises a piece of generally L-shaped relatively rigid sheet material attached at its center and one end to slots in said plate, the other end of said bell crank being connected to said rod.

22. Apparatus for aiding the locking and unlocking of an oif-center door opening and closing mechanism as claimed in claim 21 including a pair of bumpers formed of a semi-elastic mate-rial, one bumper being mounted on the end of each of said arms at the point where said arms coact with the handle of said door opening and closing mechanism.

23. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 1 wherein said rotatable means comprises a semi-circular flat cam.

24. Apparatus for aiding the locking and unlocking of an off-center door opening and closing mechanism as claimed in claim 23 wherein said slideable means comprises a plate having a pair of projecting arms, said plate being connected to said semi-circular fiat cam.

25. Apparatus for aiding the locking and unlocking of an oif-center door opening and closing mechanism as claimed in claim 24 wherein said coupling means comprises a rod for coupling said semi-circular plate cam to said lockable means.

26. Apparatus for aiding the locking and unlocking of an ofl-center door opening and closing mechanism as claimed in claim 25 including a spring means operatively coupled to said lockable means and said first rod for preventing the application of excess pressure to said rod when said lockable means is operated.

References Cited UNITED STATES PATENTS 2,725,099 11/1955 Frie et a1. l60188 J. KARL BELL, Primary Examiner US. Cl. X.R. 49278, 302 

